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We’re all used to the majority of gems being called by their name:
Diamond is diamond;

Opal is opal;

Turquoise is turquoise;

Even in it’s many different colours Topaz is still Topaz.

Emerald is emerald…well actually it’s Beryl…as is Morganite, Aquamarine, Heliodore and Goshenite! What distinguishes each of these is the colour that the gem comes in (green, pink, pale blue, yellow and colourless respectively).

Ruby, well that’s actually a form of Corundum, called Ruby only when it is red, when it is pinky orange it is called Padparadscha. All other colours of Corundum are called sapphires so you can find all kinds of sapphires, such as the green one below.

Green sapphire

Tourmaline comes in a variety of colours and several of these have particular names too. When it is red/pink it is Rubellite, green is Verdelite, blue is the fabulous Indicolite and colourless is Achroite.

Tanzanite is a form of zoisite, Morganite is a Beryl and they were both named by Tiffany and Co.

Amazonite is a type of Feldspar, as is Labradorite. Incidentally Feldspar is the most prolific mineral in the Earth’s continental crust and can be found on Mars! This is a good example of two types of mineral which are chemically related but clearly very different.

Quartz (the second most abundant mineral behind Feldspar) has another wide variation in colour, and many names or nicknames to go with it. From the yellow citrine, to stunning purple amethyst (and of course the incredible ametrine is therefore part of this family).

Another variation is green quartz, sometimes referred to as green amethyst although if we were going to be strict about it that’s not it’s real name! So we are going to go with the official Prasiolite, and here’s an example:

However the quartz pseudonyms don’t stop there, even more strangely Chalcedony (see ring below), Agate, Onyx, Jasper, Tigers Eye, Aventurine and Carnelian are all types of quartz that you might not guess from the name!

Blue Chalcedony

Smokey Quartz

Of course the feminine pink of rose quartz to the stunning brown hues of smokey quartz (ring above) and the fascinating Rutilated Quartz are also, more obviously part of the family.

Another slight confusion may arise when considering the names of gems in that often the gem quality variation of a type of mineral has a different name to the non-gem form, Csarite/Diaspore, Peridot/Olivine and Iolite/Cordierite by way of example.

We’ve looked at different materials for making jewellery but now let’s tackle the classic!

By gold we’re talking here about the genuine article, not gold coloured metal, but the element itself. Whilst we think about gold as being a durable material which will last hundreds of years (think Staffordshire Hoard perhaps) it is a dense but soft and ductile metal, which means that while the metal itself may last it is likely to have much fine detail worn off over time if exposed to harsh conditions. It is an excellent metal for jewellery making because of these properties though, and even more so because it does not tarnish in air or water, so will retain its lustre, and is not very chemically reactive.

Source: Wikipedia

Gold is generally mined from the earth, most commonly as gold nuggets, but also within rocks in veins and alluvial deposits. It an also be found as a compound with other elements but this is less common. Although it is not very reactive it does react with some elements and compounds, and the term “acid test” arises from using nitric acid to test for gold as it can dissolve base metals and silver but not gold.

Gold is of course not only used in jewellery (although nearly 50% of all gold mined is used for jewellery), it has been used in coinage and it’s understood that today around 10% of gold is used in industry and according to the World Gold Council nearly 175,100 tonnes of gold have been mined and this would fit into 21 cubic meters if it was all put together! But it is known to have been used in jewellery making for around 7000 years – unbelievable!!! It’s as popular as ever for jewellery making and 2013 saw the largest volume increase in jewellery demand for 16 years. (There are lots of interesting facts on the gold.org website if you fancy some gold trivia).

Yellow gold is still the most popular colour, but today gold is available in a diverse palette. The process of alloying—mixing other metals with pure 24 carat gold—gives malleable gold more durability, but can also be used to change its colour. All gold essentially starts out as yellow gold, different colours are created by allowing the metal with white metals. White gold is then usually plated with rhodium to create the shine and appearance we are used to. For those not familiar with white gold (…are you out there?!) be warned that this plating WILL need renewing, the regularity of this depends upon the quality of the plating and the amount you wear the item (i.e. white gold engagement ring worn all the time will need re-plating more frequently than a rarely worn pendant.

The soft warm colour of rose gold is created with the use of copper, you can find out the technical composition of different golds in a variety places but you may want to start here. There are other colours of gold created through addition of other alloys or through coatings to the surface of the gold, these are fairly rare in the UK and require a little extra care so do look at particular instructions when purchasing anything unusual and be wary of fakes!

We’ve all heard of carats and you may be familiar with the use of this as a measure for gold and gems, in gold the purity of the metal is measured in carats rather than its weight (which is measured in troy ounces). The measure of the carat is how much pure gold is alloyed with other metals. The purest gold is 24 carat and this means that there are no other metals mixed in with the gold, lower carats (eg 18 or 9 carats) contain less gold and a combination of other elements. In the UK 9 carat is the minimum, and whilst this is the least valuable as it effectively contains the least gold, it does have some advantages as it is harder and therefore more durable, whilst this makes it slightly harder to work with in terms of jewellery making it does mean it can take a bit more rough and tumble.

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What do we like…?

Well we all tend to have a favourite item of jewellery, many designers work with gold but here are a couple of our favourite items from around the web:

I love this intricate but chunky ring from Lavan Jewellery (handmade in the UK) and even better they do a massive variety of sizes.

Beautiful 9ct gold pebble necklet from Sheila Fleet, I love the tactile and texture achieved in this look. If you’re interested in jewellery influenced by nature do check out some of Sheila Fleet’s other designs, I really like the Rowan collection with subtle use of gems.

Whilst there are many different colours of diamonds (which we’ll come onto in a different post) we’re going to look specifically at alternatives to the colourless diamond. Common replicas include Cubic Zirconia, Moissanite, Petalite, Zircon and Topaz. For even cheaper prices clear glass or acrylic is often used in high street jewellery. These can all be found in incredibly clear and brilliant examples, they’re cheaper, many look similar, so how can you tell what is real? Take the well known crystal brand Swarovski, this beautiful necklace (below) is stunning in many different lights, can you really tell that it’s not diamond; and if you can does it matter? In the cases of white Zircon, Topaz and Petalite, among others, you’re still getting a real gemstone, similar mining processes and cutting, but paying nowhere near the price of a diamond. In any event to be fair can anyone really tell whether the rock around your neck is actually synthetic crystal or diamond anyway. Disadvantages of the alternatives So the obvious disadvantage of anything that isn’t diamond or one of the other really desirable gems is that it is likely to lose value, a real diamond is more likely (but not guaranteed) to gain in value over time, particularly good quality gems which are well looked after. However, turning this on its head of course you probably won’t have paid anywhere near as much for a moissanite or CZ so does it really matter, to each their own. The other obvious disadvantage is that unless you’re wearing a diamond you are not wearing one of the hardest gems known to man…this could make your item easier to scratch or damage…you might not be able to use it to carve your name onto furniture… On a serious note each gem (real or synthetic) has different refractive/fluorescence and brilliance or sparkle. This is where the real trick lies in trying to distinguish real from fake but in reality without close examination it’s unlikely that even an accredited jewellery professional is going to argue if you tell them your CZ is a diamond. There are also advantages to none diamond pieces, unless you’re particularly precious about your precious gems, synthetic or less pricy gems means you can afford either bigger pieces, or more items than you might be able to with real diamonds. They can look just as stunning (I wore CZ on my wedding day so no arguments please, but cue an opportunity to flash some wedding bling!) and chances are most people you pass in the street won’t be able to tell. After all how many of us have spent our journey to work staring at someone’s engagement ring wondering whether that giant rock is real or not…?! Ooh more importantly this means it’s more difficult to tell if that rock he got for you is real…hmmm that’s when it’s good to know a gemologist 😉

So whilst it’s lovely to gaze over diamonds and dream, what happens when you want to purchase? It’s pretty well known that the things to look for in a diamond are the C’s i.e. colour, clarity, carat weight and cut, but what does this mean in reality and is this really all there is to it?

Colour

Basically the less colour visible the higher the price (except for fancy coloured stones, but again more on coloured diamonds later). You will mostly come across the GIA grading system which uses a letter system of colour grading. D being the highest grading of colourless, descending towards Z travelling through near colourless, faint yellow, light yellow and so on. At the very basic level as the colour and grade increases the price of your stone decreases.

Clarity is defined as the degree to which a stone is free from external marks (called blemishes) and internal features (called inclusions). Like with colour the freer the stone is from blemishes and inclusions the more expensive the price tends to be. These factors, like with colour, are given grades; the GIA clarity grades start at F1 “flawless, no blemishes or inclusions” which are very rare and expensive (essentially, “we wish”). Diamonds are generally found in high street jewellery around lower grades such as SI1 & SI2 which are slightly included, ranging from easy to see under 10x magnification (i.e. using your loupe) and somewhat easy to see with your naked eye. Diamond grades end at I1-I3 (P1 -P3 is used in some countries) which are imperfect, characteristics and flaws which can be seen easily with the naked eye.

The unit of weight used for diamonds is the carat, in most cases the higher the carat weight the higher the price, a carat is a unit of weight equalling 1/5 of a gram. The weight of small diamonds are often expressed in points, with one point equalling 0.01 ct (carat) Diamond jewellery in stores may often have the total diamond weight on display which for example 1ct for a 5 stone ring will not therefore be of an equivalent value as a 1ct single stone in a ring. Also take note if the quantity is expressed in points or carats, as 0.25 points is not equivalent to 0.25 ct which is a quarter of a carat.

Cut

This refers to the proportions and finish of the stone, two of the main considerations of cut are:

Do you see brilliance all across the stone when you look through the stone face up? You should not see large dark areas.

Are you paying for excess weight? is the stone too fat basically when you look at it sideways a poorly cut stone may have a very thick appearance from the side but look much smaller from the top this will also effect the brilliance that stones gives off. Symmetry is also a consideration as this also affects the level of brilliance emitted by the stone.

Cut can be judged by the naked eye and a 10-power magnifier, but it is not as simple as it sounds (naturally!) Cut should be considered in more detail, looking at the cutting style and quality and the shape of the stone. The finish is also important as how well the cut is finished can affect sparkle and brilliance.

Whilst cut is very much about personal taste trends affect prices so at the moment round stones tend to cost more than pear, marquise and emerald cuts but this hasn’t always been the case.

Normally square shapes cost less than round as there is less wastage when the stone is being cut from its rough state, and there is usually less demand for squares. However, depending on demand in different areas of the world princess cuts (squares) have occasionally sold for more than rounds.

Anything else…?

Well in short…yes! (Sorry this is turning into a long post but we promise this is only scratching the surface, hard to do on a diamond!) Transparency is another factor to consider, the degree to which the stone is clear, hazy or cloudy as again this will alter how the stone reacts to light and therefore how it looks when being worn.

The other thing to take care of when dealing with diamonds is the treatment status i.e. whether the stone has had any external treatment since being mined. There are a number of techniques and treatments which have been developed to improve the look of white diamonds; some have been deliberate attempts to deceive buyers but with a reputable jeweller you should be able to ask about any treatments of the stone. An example is the process of using a laser to vaporize black inclusions, this leaves a fine white thread that starts at the surface and travels into the stone. This treatment is permitted but must be disclosed on any certificate obtained. Fractures and cracks can be filled with a glasslike substance that is visible only under magnification. Certain types of yellow-tinted diamonds are put through a high-temperature, high-pressure treatment (HPHT) process to make them colourless. This treatment is permanent and heat treated diamonds can only be identified in a lab.

Depending on what you’re after in a gem treatments are not necessarily something to shy away from, they can reduce the value of a stone but give you the look of a much better quality stone. One of the things you should beware of though when it comes to treatments (not only in diamonds) is that not all treatments are permanent, the filler we have mentioned above is not a permanent treatment and bad care or handling can loosen the filler or change its colour.